GEOLOGIC RECONNAISSANCE OF MINDANAO AND SULU. 497 



ground; however, there are neither ashes nor lava. The pathwaj' follows the 

 south side of a huge crevasse visible from far below, and after following 

 this for about 300 meters crosses to the north side and continues along 

 it and around its head to a knife-edged ridge leading to the summit. This 

 crevasse in some places is probably 20 meters deep and 250 wide, it has eight 

 or ten vents from which vapors containing sulphur dioxide issue. A cone of 

 fairly pure sulphur surrounds each vent ; in individual cases these deposits may 

 reach dimensions of several thousand kilos ; possibly there may be 400 metric tons 

 of this material altogether. It probablj' could not be handled conveniently. 

 A clay tablet with the inscription — 



La ilnica Expedicion a Volcan Ap6 



1880 



ilontano y Rajal 



exists at about 2,350 meters' altitude. 



Our party reached the summit at a little after noon. So far as is now known, 

 this is the highest mountain peak in the Philippine Archipelago. The altitude was 

 determined by two trials with the boiling-point method, which gave respectively 

 2,956 and 2,902 meters. The barometric reading at the first trial showed 2,811 

 meters, which number is, of course, considerably in error. The old Spanish Coast 

 and Geodetic chart of this region gives 3,143 meters, but work now being carried 

 on by the Coast and Geodetic Survey of the United States shows that the Spanish 

 work in these waters is in error. 



The records of several parties are found on the summit, the earliest encountered 

 being that of Schadenberg and Koch, 1882. None of the Montano expedition 

 of 1880 was visible and possibly the tablet at about 2.600 meters' altitude has 

 been carelessly or maliciously removed from tlie top where it was originally 

 placed. 



The highest point of the mountain, as determined by measurement, is reached 

 by crossing a low sag to the next pinnacle, and here is placed a cairn containing 

 a brass tube with a screw top marked "S. C." Inside is a neat scroll of the 

 Sierra Club of California, duly stamped with its seal and signed by its president, 

 John Miner. This scroll was deposited in the month of October of 1904, by Dr. 

 E. B. Copeland, formerly of the Bureau of Science. Our party was the first to sign 

 on the register. 



Sights^, with the ti'aii,sit, were taken at all prominent points of the 

 topography and boiling-point determinations were also made, although 

 the work was much hampered by fog. The weather cleared in the late 

 afternoon and we were able to observe the panorama from the summit. 



The Gulf of Davao was plainly visible with its island and coves, encir- 

 cled by dark green wooded mountains and long volcanic slopes. The Eio 

 Grande cuts across the foreground as a silver streak, extending far in the 

 midst of many folds of green which continue without break to the skyline 

 to the westward. The vast extent of the jungle in this island is very 

 strongly impressed upon the observer. Mount Matutan is visible some 

 63 kilometers away, appearing as an isolated cone. It was sighted 

 with a level, and appears to be but little lower, even at that distance, 

 than the point on which we stood. If the curvature of the earth is taken 



